Gene expression, antiparasitic activity, and functional evolution of the drosomycin family

• Published in: Molecular immunology Vol. 45; no. 15; pp. 3909 - 3916
• Main Authors: Tian, Caihuan, Gao, Bin, Rodriguez, Maria del Carmen, Lanz-Mendoza, Humberto, Ma, Bo, Zhu, Shunyi
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.09.2008
• Subjects: Amino Acid Sequence; Animals; Antifungal Agents - metabolism; Antifungal Agents - pharmacology; Antifungal peptide; Antimalarials - metabolism; Antimalarials - pharmacology; Defensins - genetics; Defensins - metabolism; Defensins - pharmacology; Drosomycin-2; Drosophila; Drosophila melanogaster; Drosophila melanogaster - embryology; Drosophila melanogaster - growth & development; Drosophila melanogaster - immunology; Drosophila melanogaster - metabolism; Drosophila Proteins - genetics; Drosophila Proteins - metabolism; Drosophila Proteins - pharmacology; Escherichia coli; Evolutionary epitopes; Fungi - drug effects; Gene Expression Regulation, Developmental; Immunity, Innate; Models, Molecular; Molecular Sequence Data; Parasite; Phylogeny; Plasmodium berghei; Plasmodium berghei - drug effects; Protein Conformation; Recombinant Proteins - pharmacology; Parasite; Drosomycin-2; Antifungal peptide; Plasmodium berghei; Drosophila; Evolutionary epitopes
• ISSN: 0161-5890; 1872-9142
• DOI: 10.1016/j.molimm.2008.06.025

Drosophila employs various antimicrobial peptides as effective weapons to defend against diverse pathogens. Drosomycin is an inducible antifungal peptide initially isolated from the Drosophila melanogaster haemolymph. Here we report the expression pattern of seven drosomycin genes in four different developmental stages (egg, larva, pupa and adult). Results show that drosomycin and drosomycin-2 are expressed in larva, pupa and adult, whereas drosomycin-1 and drosomycin-6 were not detected in all the stages. Moreover, all the seven drosomycin genes are shut off in egg. Functional comparison of recombinant drosomycin and drosomycin-2, both with identical expression pattern, produced from Escherichia coli, revealed their significant differences in potency against a specific fungal species. In addition, we found for the first time that drosomycin and drosomycin-2 both are antiparasitic peptides which show inhibitory effect on the ookinete development of the parasite Plasmodium berghei with differential potenc y. Functional differentiation between them was further evaluated by evolutionary trace analysis which identified two evolutionary epitopes (named α- and γ-patch, respectively) and an important site in the m-loop. Substitutions in these regions are possibly associated with the antifungal and antiparasitic potency difference among members of the drosomycin family.